Information architecture is organizing information so that it is easy to use. If we apply paradigm of design we learned last week, information architecture deals with the paradigm of engineering and paradigm of usability. (You can see nice pyramid about paradigm of design here) So it is about how to make information easy to find. So many interesting theories like information foraging is used. It will be especially useful, when there is many information in certain places, when the user will have to guess where the related information is located. Providing self-relevant categories and many hints(scent) about where the info may lies is key task for the information architect. There can be a really wide variety of category over specific items. However some of the user-centered techniques for creating such architecture includes card sorting ,closed card sorting, similarity matching. They request users to categorize and label various items. The reason these are user-centered is that from various categorization available, designer follows what the customer thinks naturally. One concept useful in this approach that is not discussed in the article is the concept of user’s mental model and designer’s representation model. By making these similar, we can achieve optimal organization. And that’s why we designers are interested in the model in user’s mind. There are many topology certain sites can have. For example there is hierarchy(tree), linear (sequence), matrix, full mesh, arbitrary network and hybrid. Even though there is no absolute answer to the topology, a topology is adequate at certain situation. One thing I would like to note is the horizontal vs vertical organization. If there is many contents, horizontal organization with many links at certain level which means short required level. Also the vertical organization means at certain level there is small number of links, which means deep required level. It seems horizontal organization performs generally better than the vertical organization. It seems because there are many choices, the probability of error also increases. So in vertical organization where the user has to make many choices, there can be more errors. So heuristically sublevel below 3 is now recommended.